Traditionally, a technique for reducing power consumption in a standby state of a device with a communication function is proposed (see, for example, PTL 1). The device of PTL 1 includes a main CPU which processes an image signal and also includes a network CPU, a sub-CPU, and a network sub-CPU. In this device, power supplying states such as off, standby state A, standby state B, standby state C, active standby, warm-up, and ON, are prepared. In these power supplying states, power supply to each CPU is controlled, thus achieving power saving. For example, in the standby state A, which is the state where power saving is emphasized most, power is supplied only to the sub-CPU, which detects a power ON instruction. Meanwhile, in the standby state B, which is the state where power saving is emphasized next to the standby state A, power is fed to the network sub-CPU to enable a network communication function only for wired communication. Moreover, in the standby state C, a wireless communication function is enabled. In the standby states B and C, where the network communication function is enabled, wired or wireless data communication can be executed and processing of received data can be carries out. Power supply to the other CPUs is stopped, thus achieving power saving.